geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Clinical cerebral microdialysis: a methodological study


, : Clinical cerebral microdialysis: a methodological study. Journal of Neurosurgery 93(1): 37-43

Object: Clinical microdialysis enables monitoring of the cerebral extracellular chemistry of neurosurgical patients. Introduction of the technique into different hospitals' neurosurgical units has resulted in variations in the method of application. There are several variables to be considered, including length of the catheter membrane, type of perfusion fluid, flow rate of perfusion fluid, and on-line compared with delayed analysis of samples. The objects of this study were as follows: 1) to determine the effects of varying catheter characteristics on substance concentration; 2) to determine the relative recovery and true extracellular concentration by varying the flow rate and extrapolating to zero flow; and 3) to compare substance concentration obtained using a bedside enzyme analyzer with that of off-line high-performance liquid chromatography (HPLC). Methods: A specially designed bolt was used to conduct two adjacent microdialysis catheters into the frontal cortex of patients with head injury or poor-grade subarachnoid hemorrhage who were receiving ventilation. One reference catheter (10-mm membrane, perfused with Ringer's solution at 0.3 mul/minute) was constant for all studies. The other catheter was varied in terms of membrane length (10 mm or 30 mm), perfusion fluid (Ringer's solution or normal saline), and flow rate (0.1-1.5 mul/minute). The effect of freezing the samples on substance concentration was established by on-line analysis and then repeated analysis after storage at -70degreeC for 3 months. Samples assayed with the bedside enzyme analyzer were reassessed using HPLC for the determination of glutamate concentrations. Conclusions: Two adjacent microdialysis catheters that were identical in membrane length, perfusion fluid, and flow rate showed equivalent results. Variations in perfusion fluid and freezing and thawing of samples did not result in differences in substance concentration. Catheter length had a significant impact on substance recovery. Variations in flow rate enabled the relative recovery to be calculated using a modification of the extrapolation-to-zero-flow method. The recovery was approximately 70% at 0.3 mul/minute and 30% at 1 mul/minute (10-mm membrane) for all analytes. Glutamate results obtained with the enzyme analyzer showed good correlation with those from HPLC.

US$19.90

PMID: 10883903

DOI: 10.3171/jns.2000.93.1.0037


Other references

Miller, L.M.; Escabi, M.A.; Read, H.L.; Schreiner, C.E., 1998: Synchrony in the auditory thalamocortical system of the cast, and its modulation with dynamic ripple stimulation. Society for Neuroscience Abstracts 24(1-2): 1879

Dux E.; Temesvari P.; Szerdahelyi P.; Nagy A.; Kovacs J.; Joo F., 1987: Protective effect of antihistamines on cerebral edema induced by experimental pneumothorax in newborn piglets. As a consequence of general hypoxaemia evoked experimentally by bilateral pneumothorax, brain oedema of vasogenic type developed in newborn piglets after 4 h survival. Histamine receptor antagonists, mepyramine (H1-receptor blocker), metiamide, ci...

Armstrong, D.; Morton, V.; Friedman, M.H.; Steger, L.; Tully, J.G., 1972: Canine pneumonia associated with mycoplasma infection. During surgical experiments several dogs developed pneumonia. In most cases cultures made from infected tissues yielded one or more types of Mycoplasma. These were classified as belonging to Groups A, B, C, C' or D. Serological examination of...

Stalder H.A., 1964: Quarzfund vom Taminser Calanda. Describes the optical properties, habit, twinning, and inclusions of a sample of lamellar quartz crystals from fissures in Triassic dolomite on the southern slope of the Taminser Calanda (north of Vaettis), east Switzerland, obtained for the colle...

Varma, A.; Appleton, D.L.; Nusca, A.; Lipinski, M.J.; Goudreau, E.; Cowley, M.J.; Wittkamp, M.; Vetrovec, G.W.; Abbate, A., 2010: Iron deficiency anemia and cardiac mortality in patients with left ventricular systolic dysfunction undergoing coronary stenting. The aim of this study was to assess cardiac mortality in patients with reduced ejection fraction (EF< or =45%) and anemia (Hb< or =12 g/dL) undergoing coronary stenting and to investigate whether iron-deficiency anemia influenced outcome whe...

Fozia, A.; Muhammad, A.Zia.; Muhammad, A.; Zafar, M.Khalid., 2009: Effect of chromium on growth attributes in sunflower (Helianthus annuus L.). Heavy metal soil pollution takes place when the metal concentration of soil exceeds natural background level and causes ecological destruction and deterioration of the environment. In the present study, a pot experiment was conducted to evaluate t...

Landgrebe, B.H., 1999: Stellate ganglion blocks and vagus nerve stimulation in the treatment of epilepsy-Noradrenergic and cholinergic interactions. Epilepsia 40(SUPPL 2): 296-297

Chudley, A.E.; Ninan, A.; Young, G.B., 1981: Neurologic signs and hypophosphatemia with total parenteral nutrition. Two infants, 11 and 12 months old, are described in detail. Both had severe gastroenteritis which required total parenteral nutrition, followed by unusual neurological signs and extreme hypophosphataemia. With phosphorus replacement, the metabolic...

Murrell K.D.; Cates M.D., 1970: Seasonal periodicity of ecto parasites of rattus rattus tanezumi from taiwan. Journal of Medical Entomology 7(3): 367-370

Ito S.; Ito Y.; Nishikawa M.; Tokura T.; Yamane A.; Yamagishi K.; Miki H., 1989: The effect of trabeculotomy and laser trabeculoplasty on outflow structures. Investigative Ophthalmology & Visual Science 30(3 SUPPL): 357